1 Field of the Invention
The present invention relates to a system for automatically feeding a chemical liquid to water circulating through a heat exchange circuit in a cooling tower so as to prevent red rust and/or fur from occurring in the circulating water.
2 Statement of the Prior Art
Such systems heretofore available in the art are broken down into large, medium and small sizes, and all rely upon automatic water-feeding means comprising a float valve or the like provided in a water reservoir, which is actuated to sense a reduction in a water level therein and return the water level to the predetermined level so as to constantly maintain a given amount of water circulating through a heat exchange circuit in a cooling tower.
In the system of a large size, an electrically operated pump in operative association with such automatic water-feeding means is actuated to feed the predetermined amount of a chemical liquid on regular or automatic basis.
In the systems of medium and small sizes, however, it is still required for maintenance workers to feed a chemical liquid in a manual manner.
With the large-sized system it is possible to regularly feed a specific quantity of a chemical liquid to a water reservoir in which circulating water is stored. However, additional provision of an electrically operated pump needs additional facilities and costs. On the other hand, the medium- and small-sized systems are now under pressure of increased initial investment.
Of the medium- and small-sized systems, some systems relying upon maintenance workers are inexpensive as compared with systems relying upon electrically operated pumps. Since cooling towers are generally installed on elevated spots such as the roofs of high buildings, however, not only is feeding work dangerous but also difficulty is encountered in regular feeding of a constant amount of a chemical liquid due to the need of man power.